[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]
Avian Dis. 2018 Dec;62(4):373-380. doi: 10.1637/11891-050418-Reg.1.
Environmental Sampling Survey of H5N2 Highly Pathogenic Avian Influenza-Infected Layer Chicken Farms in Minnesota and Iowa.
Lopez KM1, Nezworski J2, Rendahl A1, Culhane M1, Flores-Figueroa C3, Muñoz-Aguayo J3, Halvorson DA1, Johnson R1, Goldsmith T1, Cardona CJ4.
Author information: 1 College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108. 2 Blue House Veterinary, 145 West Yellowstone Trail, Buffalo, MN 55314. 3 Mid-Central Research and Outreach Center, University of Minnesota, 1802 18th St. Northeast, Willmar, MN 56201. 4 College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108, firstname.lastname@example.org.
Abstract in English, Spanish
Respiratory secretions, feces, feathers, and eggs of avian influenza-infected hens provide ample sources of virus which heavily contaminate barn and farm environments during a disease outbreak. Environmental sampling surveys were conducted in the Midwestern United States on affected farms during the 2015 H5N2 highly pathogenic avian influenza (HPAI) outbreak to assess the degree of viral contamination. A total of 930 samples were obtained from various sites inside and outside layer barns housing infected birds and tested with real-time reverse transcriptase PCR. The distribution and load of viral RNA in barns in which most birds were dead at the onset of depopulation efforts (high-mortality barns) were compared with those of barns in which birds were euthanatized before excess mortality occurred (normal-mortality barns). A statistically significant difference was seen between cycle threshold (Ct) values for samples taken of fans, feed troughs, barn floors, barn walls, cages, manure-associated locations, barn doors, egg belts, and the exterior of high-mortality vs. normal-mortality barns. In high-mortality barns, sample sites were found to be the most to least contaminated in the following order: cages, manure-associated locations, barn floors, egg belts, feed troughs, barn doors, barn walls, fans, exterior, and egg processing. Significant changes in Ct values over time following HPAI detection in a barn and depopulation of birds on an infected farm were observed for the manure-associated, barn floor, barn wall, and fan sampling sites. These results show that high mortality in a flock as a result of HPAI will increase contamination of the farm environment. The results also suggest optimal sampling locations for detection of virus; however, the persistence of RNA on highmortality farms may delay the determination that adequate sanitization has been performed for restocking to take place.
KEYWORDS: barn; contamination; disinfection; egg layers; environmental sampling; highly pathogenic avian influenza; virus
PMID: 31119921 DOI: 10.1637/11891-050418-Reg.1
Keywords: Avian Influenza; H5N2; Poultry; USA; Minnesota; Iowa.